{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1921-2JE11","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1921-2JE11","canonicalUrl":"https://aoctrl.com/siemens/3RH1921-2JE11","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1921-2JE11","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS auxiliary switch, 1 NO + 1 NC, spring-loaded terminals, snap-on mounting for S0 contactors, 10 mm wide, 71 mm deep.","salesMarkdown":"## What this switch does on a contactor The Siemens 3RH1921-2JE11 is a SIRIUS auxiliary switch block designed to snap onto S0-frame contactors (3RT1 series) and contactor relays. It adds one normally-open and one normally-closed instantaneous contact, wired via spring-loaded terminals. The 10 mm width means it tucks in alongside the contactor without widening the DIN-rail footprint beyond what the S0 frame already occupies. Rated for 6 kV surge voltage and 500 V insulation at pollution degree 3, it handles control-circuit isolation in standard industrial panels. The mirror-contact function per IEC 60947-4-1 (confirmed with 3RT1 contactors) means the NC position mechanically mirrors the main contact position — relevant for safety circuits where you need positive indication that the power contacts have opened. Snaps directly onto the contactor body — no DIN rail needed for the switch itself, though the contactor mounts on the rail. The second can be mounted laterally, so you can stack multiple auxiliary blocks on one contactor if the control scheme demands more than one NO/NC pair. Spring-loaded terminals accept 2x (0.5... 2.5 mm²) solid or stranded, or 2x (20... 14 AWG). Finely stranded with core-end processing goes up to 1.5 mm². Strip and push; no screw torque to check. The IP20 front protection keeps fingers out but the block is inside the panel anyway. ## Durability and contact reliability Rated for 5 million mechanical operating cycles typical. The 0.3 A draw at 24 V, 48 V, or 60 V is the coil consumption of the contactor it rides on — the auxiliary contacts themselves carry the load of the control circuit they switch.","metaTitle":"Siemens 3RH1921-2JE11 SIRIUS Auxiliary Switch, 1 NO + 1 NC,","metaDescription":"Siemens 3RH1921-2JE11 SIRIUS auxiliary switch for S0 contactors. 1 NO + 1 NC, spring-loaded terminals, snap-on mounting. Active production, quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"71 mm","Width":"10 mm","title":"3RH1921-2JE11","Height":"72.5 mm","at 24 V":"0.3 A","at 48 V":"0.3 A","at 60 V":"0.3 A","description":"second lateral Auxiliary switch, 1 NO, 1 NC, spring-type terminal, for contactors 3RT1","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"snap-on mounting","Product Category":"Auxiliary switch","Size Of Contactor":"S0","Solid Or Stranded":"2x (0.5 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Product Designation":"auxiliary switch","Suitability For Use":"Contactor relay and power contactor","Design Of The Product":"second can be mounted laterally","Instantaneous Contact":"1","Substance Prohibitance (Date)":"03/01/2017","protection class IP on the front":"IP20","Surge Voltage Resistance Rated Value":"6 kV","for AWG cables for auxiliary contacts":"2x (20 ... 14)","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²)","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","mirror contact according to IEC 60947-4-1":"Yes; with 3RT1","Finely Stranded Without Core End Processing":"2x (0.5 ... 2.5 mm²)","Mechanical Service Life (Operating Cycles) Typical":"5 000 000","Type Of Electrical Connection For Auxiliary And Control Circuit":"spring-loaded terminals","insulation voltage with degree of pollution 3 at AC rated value":"500 V","number of CO contacts of auxiliary contacts instantaneous contact":"0","AWG number as coded connectable conductor cross section for auxiliary contacts":"20 ... 14"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$19.05","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/e5262ff11356735a89bf0745a6bf446b.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=319841&mlfb=3RH1921-2JE11"},"ai":{"faq":[{"question":"What contactor does 3RH1921-2JE11 fit?","answer":"It snaps onto S0-frame contactors in the 3RT1 series. The switch is sized for S0 contactors and mounts directly to the contactor body."},{"question":"What does the mirror-contact feature mean?","answer":"The NC contact is a mirror contact per IEC 60947-4-1, meaning its position mechanically mirrors the main contact position. This is used in safety circuits to confirm the power contacts have opened."},{"question":"Where can I buy 3RH1921-2JE11?","answer":"Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"Will 3RH1921-2JE11 drop into a panel wired for 3RH2122-2AV60?","answer":"No — the 3RH2122-2AV60 is a full auxiliary contactor (45 mm wide, S00 frame) with four contacts and screw/snap-on DIN mounting. The 3RH1921-2JE11 is a 10 mm auxiliary switch block that snaps onto an S0 contactor. They are not footprint-compatible; the panel would need a different contactor frame."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1921-2JE11","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3RH1921-2JE11 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}